In the past some shortening of processing time for light-sensitive materials for photography has been achieved as a result of progress relating to light-sensitive materials and processing agents. In general, photographs by amateur or professional, need only to be processed taken quickly enough to suit convenience. However, in the printing field, especially in the case of newspapers etc., information has to be communicated immediately and thus a reduction in processing time of light-sensitive material is clearly desirable. Moreover, in the case of light-sensitive materials which are used in the course of medical treatment, it is necessary in emergencies to make a diagnosis and take action within seconds, and thus here a reduction in processing time is of the greatest importance.
Development time, fixing time, washing time and drying time can be reduced in order to shorten the processing time. Sometimes the activity of the development bath is increased by increasing the concentration of developing agent, increasing the pH, or by raising the processing temperature, while in other cases the development properties of the silver halide emulsions themselves are improved. Such methods are already well known. However, raising the activity of the development bath can result in increased costs and it can result in a reduction in the stability of the development bath itself over a period of time, yet such systems do not always represent an increase in commercial value. On the other hand, the washing time and drying time are largely dependent on the thickness and the degree of swelling of the coated film on of the light-sensitive material. These times can be shortened by increasing the degree of crosslinking of the gelatin with the use of adequate film hardening agents before treatment, but this method reduces the covering power of the silver halide and thus the amount of silver coated may have to be increased or there may be a reduction of sensitivity and a reduction in the rate of development and, moreover, the method results in a lowering of the fixing rate. Thus, even though there are methods available for shortening the processing time for each of these operations, in virtually all cases the method of shortening is accompanied by significant disadvantages.
In direct X-ray photographic films for medical purposes the emulsion layers are generally coated on both sides of the support in order to reduce the level of exposure of the body to harmful X-rays, and considerable amplification is achieved by taking pictures using sensitizing screens on both sides of the light-sensitive material. The problem with such a photography system is known as "crossover". This means that the light which is emitted by a sensitizing screen not only exposes the silver halide emulsion layer on the side adjacent to the screen, but also exposes the emulsion layer on the opposite side with the scattered light which has passed through the emulsion layer and the support. This "crossover" results in an image of reduced sharpness.
On the other hand, techniques for improving sharpness by adding magenta dyes or yellow dyes to ortho type light-sensitive materials have been developed, as described in U.S. Pat. No. 4,130,429 and JP-A-No. 61- 116354 and JP-A-No. 61-116349. (the term "JP-A" as used herein refers to an unexamined published Japanese patent application). However, when a dye is simply added to the silver halide emulsion layers it inevitably has the effect of reducing the photographic sensitivity due to optical absorption. Hence, methods in which these dyes are added to intermediate layers between the silver halide emulsion layers and the support have sometimes been adopted in the industry. But, with the provision of just a simple intermediate layer, the dyes diffuse during the coating of the emulsion layers, and thus there is still some loss of photographic sensitivity. Moreover, to make matters even worse, gelatin or some other binder has to be used to coat the intermediate layer, and the increase in the amount of binder used inevitably has an adverse effect on the drying properties of the light-sensitive material.
To overcome the above problems, it has been proposed to use basic polymeric mordants to fix water soluble dyes, which dyes can be decolorized during photographic processing in the subbing layer of the support. Such methods have been disclosed in JP-A-No. 62-70830 and JP-A-No. 55-33172. These methods are very effective toward fulfilling objectives of the present invention, but they fall short because in these methods the subbing layer has a coated gelatin weight of not more than 0.5 g/m.sup.2, and when a basic polymeric mordant is coated in a gelatin layer as lightly as this, the surface of the subbing layer becomes irregular. That is, streaks, ladder and comet etc. occur to an intolerable extent. Hence, it is not possible to use the above methods to achieve excellent performance.